Stormlight

Stormlight is the fundamental magical energy of Roshar, a luminous power carried by the highstorms and stored within gemstones. It is the fuel of Surgebinding, the source of the Knights Radiant's powers, and one of the most important forces in the world of The Stormlight Archive. Stormlight is a manifestation of the Investiture of the Shard Honor, one of the powers shaping the Cosmere.

Description

Stormlight appears as a glowing, smoke-like radiance that escapes in luminous wisps from any gemstone or person holding it. A person infused with Stormlight feels invigorated, strong, and alert, and the light visibly streams from their skin. Held Stormlight constantly leaks away and must be replenished, so it cannot be hoarded indefinitely within a living person.

Storing Stormlight

Gemstones are charged with Stormlight by being exposed to a highstorm. The size and quality of a gem determine how much it can hold. Charged gemstones, called spheres when minted as currency, glow with captured light and serve simultaneously as money, light sources, and reservoirs of power. Over time, uncharged gems left out of the storms go dun.

Mechanics

Surgebinders -- the Knights Radiant -- draw Stormlight into their bodies and burn it to fuel their powers, the Surges. Stormlight also grants enhanced healing, allowing Radiants to recover from wounds at a speed impossible for ordinary people. It can power Fabrials as well, the technological devices that harness captured Spren.

Significance

As the lifeblood of Surgebinding and the Knights Radiant, Stormlight is central to the magic, economy, and warfare of Roshar, and its connection to Honor and the highstorms ties it to the deepest workings of the world.